1. Field of the Invention
The present invention relates to a film feeder for a camera capable of feeding out of a cartridge a film wound around the shaft of a spool in the cartridge by rotating the spool shaft of the film loaded cartridge.
2. Related Background Art
For example, a film cartridge given below is disclosed in U.S. Pat. No. 4,832,275. This cartridge comprises a cylindrical portion accommodating the shaft of a spool with a film wound around it, and a feeding out portion provided extendedly in the tangential direction of the cylindrical portion with which this feeding out portion is integrally constructed. In the feeding out portion, the leading end of the film is accommodated in a linearly state. The, the film is not exposed from this cartridge unless the cartridge is loaded into the camera.
As the camera for which a cartridge of this kind is usable, the one such as given below has been proposed. When the cartridge is loaded into the main body of such type of camera, the shaft of the spool (with a film wound around it) is first caused to rotate and thrust the film out of the cartridge to the side of its wind up spool (this is called thrust motion). Subsequently to this, the leading end of the film is wound around the wind up spool in the main body of the camera for the usual winding motion; thus making the camera ready for photographing.
However, the above-mentioned thrust motion is actuated in such a manner that when the spool shaft in the cartridge is rotated, the film is given a thrust in the cartridge, and the film is pushed out by its own thrusting strength. Therefore, if a load is applied to the leading end of the film by the friction or the like of the film rail, for example, film jamming is caused in the cartridge, thus hindering the actuation of the thrust motion. Then, there is a good possibility that the subsequent winding operation fails. A problem such as this can be prevented to a certain extent if the film feed speed is slowed down when the thrust is exerted. Nevertheless, a complete prevention cannot be anticipated. In addition, there is a disadvantage that it takes a longer time before the camera is ready for photographing subsequent to loading the cartridge into the camera due to the slowing down of the thrust speed.